轮船 originally referred to paddle-wheel steamships (the 轮 meaning 'wheel'). Though modern ships no longer use paddle wheels, the name stuck. It now generally means any large ship.
usage
Transportation vocabulary: 轮船 (ship), 飞机 (airplane), 火车 (train), 汽车 (car), 自行车 (bicycle). Use 坐 + vehicle to say 'take/ride'.